EP1632951B1 - Magnetische Speicherzelle und Methode zu Herstellung derselben - Google Patents
Magnetische Speicherzelle und Methode zu Herstellung derselben Download PDFInfo
- Publication number
- EP1632951B1 EP1632951B1 EP05019439A EP05019439A EP1632951B1 EP 1632951 B1 EP1632951 B1 EP 1632951B1 EP 05019439 A EP05019439 A EP 05019439A EP 05019439 A EP05019439 A EP 05019439A EP 1632951 B1 EP1632951 B1 EP 1632951B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- layer
- wiring
- magnetic
- semiconductor
- write
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C11/00—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor
- G11C11/02—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements
- G11C11/16—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements using elements in which the storage effect is based on magnetic spin effect
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y10/00—Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11C—STATIC STORES
- G11C11/00—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor
- G11C11/02—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements
- G11C11/16—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements using elements in which the storage effect is based on magnetic spin effect
- G11C11/165—Auxiliary circuits
- G11C11/1675—Writing or programming circuits or methods
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10B—ELECTRONIC MEMORY DEVICES
- H10B61/00—Magnetic memory devices, e.g. magnetoresistive RAM [MRAM] devices
- H10B61/20—Magnetic memory devices, e.g. magnetoresistive RAM [MRAM] devices comprising components having three or more electrodes, e.g. transistors
- H10B61/22—Magnetic memory devices, e.g. magnetoresistive RAM [MRAM] devices comprising components having three or more electrodes, e.g. transistors of the field-effect transistor [FET] type
Definitions
- the present invention relates to a magnetic memory, which stores data in a magnetoresistive effect element and a manufacturing method thereof.
- MRAM Magnetic Random Access Memory
- DRAM Dynamic Random Access Memory
- SRAM Static RAM
- the MRAM is superior in access speed, reliability, power consumption and so on. Accordingly, the MRAM may perform both of the functions as a volatile memory such as DRAM and SRAM and as a nonvolatile storage such as flash EEPROM and hard disk device.
- An information apparatus which is capable of, so called, ubiquitous computing enabling information processing anytime, anywhere, is now progressively under development. The MRAM is expected to perform as a key device in such information apparatus.
- Fig. 39A is a side sectional view showing an example of structure of a memory area 100 in a conventional MRAM.
- the conventional MRAM is equipped with a plurality of wirings 102 extending in one direction and a plurality of wirings 104 extending in the direction crossing the wirings 102.
- the memory area 100 is formed in every area where the wirings 102 and 104 cross each other.
- Each memory area 100 has a tunneling magnetoresistive element (referred to as TMR element) 101, which utilizes the tunneling magnetoresistive (TMR) effect.
- TMR element tunneling magnetoresistive element
- the TMR element 101 includes a first magnetic layer (magneto-sensitive layer) 101a of which magnetizing direction A changes depending on the external magnetic field, a second magnetic layer 101c of which magnetizing direction B is fixed by an antiferromagnetic layer 101d and a nonmagnetic insulating layer 101b sandwiched between the first magnetic layer 101a and the second magnetic layer 101c.
- a first magnetic layer (magneto-sensitive layer) 101a of which magnetizing direction A changes depending on the external magnetic field a second magnetic layer 101c of which magnetizing direction B is fixed by an antiferromagnetic layer 101d and a nonmagnetic insulating layer 101b sandwiched between the first magnetic layer 101a and the second magnetic layer 101c.
- the resistant value in the thickness direction of the TMR element 101 varies depending on the magnetizing direction A in the first magnetic layer 101a and the magnetizing direction B in the second magnetic layer 101 c; i.e., whether the directions are parallel or anti-parallel with each other. Accordingly, to read the binary data from the TMR element 101, the transistor 105 is set to the conductive status to flow the current from the wiring 102 connected to the first magnetic layer 101a to the wiring 103 connected to the second magnetic layer 101c. Based on the current value or the potential difference between the first magnetic layer 101a and the second magnetic layer 101c, it is determined whether which value of the binary data is recorded.
- Patent Documents 1 and 2 The same configurations as that of the above MRAM are disclosed in, for example, Patent Documents 1 and 2.
- the magnetizing direction A of the first magnetic layer 101a is inverted only in the TMR element 101 which is given with the magnetic field from both of the wirings 102 and 104.
- the wirings 102 and 104 provide the magnetic field to every TMR element 101 disposed along the respective extending direction. Accordingly, there is a possibility that, in the TMR element 101 other than a target TMR element 101 to be written with binary data, the magnetizing direction A of the first magnetic layer 101a could be erroneously inverted by the magnetic field from the wiring 102 or 104.
- a magnetic memory disclosed in the patent document 3 is known.
- This magnetic memory is equipped with a TMR element for each memory area (memory cell), a wiring (cell bit line) for flowing the write current to the TMR element and a transistor connected to the cell bit line.
- Patent document 1 Japanese Patent Application Laid-open No. 2001-358315
- Patent document 2 Japanese Patent Application Laid-open No. 2002-110938
- Patent document 3 Japanese Patent Application Laid-open No. 2004-153182
- the TMR elements are disposed between the wirings (for example, the wirings 102 in Fig. 39A , or bit lines BL in the patent document 3 etc), which extend through pluralities of memory areas and the substrate.
- the TMR elements are disposed within the layer (wiring layer) in which a wiring system extending over plural memory areas is formed.
- a semiconductor element area such as a transistor for controlling the current for reading the binary data from the TMR element (for example, the transistor 105 in Fig.
- ferromagnetic material such as Mn, Fe, Ni and Co diffused (migration) from the TMR element into the wiring layer gradually reaches to the transistor an the substrate surface as time passes, mixes with another dopant (contamination), causing a deterioration of the electrical characteristics of the transistor. Accordingly, the life of the MRAM is largely reduced. Also, in the manufacturing process of the MRAM, there is a possibility that ferromagnetic material is mixed into the semiconductor element area formed on the substrate surface.
- US Patent 2003/0081454 A1 provides a memory cell, a memory circuit block, a data writing method, and a data reading method which realize a reduction in the number of metal layers, cost, and the chip size and an increase of production yields and product reliability.
- An object of the present invention is to provide a manufacturing method of a magnetic memory capable of reducing the diffusion of the ferromagnetic material into semiconductor element area, and a magnetic memory capable of preventing the ferromagnetic material from being mixed into the semiconductor element area in the manufacturing process thereof.
- a magnetic memory according to the present invention is a magnetic memory having a plurality of memory areas disposed in two-dimensional configuration of m rows and n columns (m and n are integers of 2 or more), comprising:
- the wiring layer which includes the first wiring corresponding to each column of the memory areas and the second wiring corresponding to each row, is formed.
- the layer (magnetic material layer) including the TMR element and the layer (semiconductor layer) including the semiconductor element area by sandwiching another layer (wiring layer), the ferromagnetic material diffused from the TMR element hardly reaches to the semiconductor layer. Accordingly, the diffusion of the ferromagnetic material into the semiconductor area constituting the semiconductor write switching device can be reduced.
- the process preparing the magnetic material layer and the process forming the wiring layer and the semiconductor layer can be separated from each other. Therefore, the TMR element can be formed in a state that the wiring layer protects the semiconductor write switching device. Accordingly, in the manufacturing process, the ferromagnetic material can be prevented from mixing into the semiconductor area constituting the semiconductor write switching device.
- the second wiring electrically connected to the control terminal of the semiconductor write switching device includes such a mode in which a part of the second wiring commonly serves as the control terminal (electrode) of the semiconductor writing device.
- the magnetic memory may includes an anti-diffusion layer, which is formed between the magnetic material layer and the semiconductor layer, for preventing an element included in the magnetoresistive effect element from diffusing into the semiconductor layer. Owing to this, the diffusion of the ferromagnetic material into the semiconductor area constituting the semiconductor write switching device can be reduced more efficiently. In the manufacturing process, the ferromagnetic material can be prevented more efficiently from mixing into the semiconductor area constituting the semiconductor write switching device.
- the anti-diffusion layer may include at least one element selected from a group consisting of Ti and Ru. Owing to this, in the anti-diffusion layer, the function to prevent the element included in the magnetoresistive effect device from diffusing into the semiconductor layer can be appropriately achieved.
- the magnetic material layer may further include a read wiring, which is provided to each of the plurality of memory areas and electrically connected to the magnetoresistive effect element, for flowing a read, current to the magnetoresistive effect element
- the semiconductor layer further includes a semiconductor area constituting a semiconductor read switching device for controlling the conduction of the read current in the read wiring in each of the plurality of memory areas. Owing to this, the binary data stored in the TMR element can be appropriately read out.
- a wiring layer is sandwiched. Accordingly, the diffusion of the ferromagnetic material into the semiconductor area constituting the semiconductor read switching device, which is a kind of a semiconductor element area, can be reduced. And further, in the manufacturing process, it is possible to prevent the ferromagnetic material from mixing into the semiconductor area constituting the semiconductor read switching device.
- a manufacturing method of the magnetic memory according to the present invention is a manufacturing method of a magnetic memory having a plurality of memory areas disposed in two-dimensional configuration of m rows and n columns (m, n are integers of 2 or more), comprising: a semiconductor layer forming process for forming a semiconductor layer; a wiring layer forming process for forming a wiring layer on the semiconductor layer; and a magnetic material layer forming process for forming a magnetic material layer on the wiring layer, wherein the semiconductor layer forming process includes a process for forming a semiconductor area constituting a semiconductor write switching device in each of the plurality of memory areas in the semiconductor layer, the wiring layer forming process includes a process for forming a first wiring corresponding to each column of the plurality of memory areas and a second wiring, which is provided corresponding to each row of the plurality of memory areas and electrically connected to a control terminal of the semiconductor write switching device included in each of the memory areas in the corresponding row, in the wiring layer, the magnetic material forming process includes a process for forming
- the above-described manufacturing method of the magnetic memory comprises the semiconductor layer forming process including the process forming the semiconductor area constituting the semiconductor write switching device which is a kind of a semiconductor element area, the wiring layer forming process including the process forming the first and second wirings, and the magnetic material layer forming process including the process forming the TMR element.
- the process to form the semiconductor area constituting the semiconductor write switching device, the process to form the first and second wirings and the process to form the TMR element are perfectly separated from each other.
- the wiring layer blocks the ferromagnetic material. Accordingly, the ferromagnetic material can be prevented from mixing into the semiconductor area constituting a semiconductor write switching device
- the diffusion of the ferromagnetic material into the semiconductor element area can be reduced. Also, according to the manufacturing method of the magnetic memory of the present invention, the ferromagnetic material can be prevented from mixing into the semiconductor element area in the manufacturing process thereof.
- Fig. 1 is a diagram schematically showing the entire configuration of a magnetic memory in accordance with one embodiment.
- Fig. 2 is an enlarged section of a memory section showing a sectional configuration taken along the line direction.
- Fig. 3 is an enlarged section of the memory section taken along the line I-I in Fig. 2 .
- Fig. 4 is an enlarged section of the memory section taken along the line II-II in Fig. 2 .
- Fig. 5 is a sectional diagram of a memory area showing a TMR element and periphery structure thereof along the row direction.
- Fig. 6 is a sectional diagram of a memory area showing the TMR element and periphery structure thereof along the column direction.
- Fig. 7A is a diagram showing the operation in the periphery of the TMR element in the memory area
- Fig. 7B is a diagram showing the operation in the periphery of the TMR element in the memory area.
- Fig. 8A is a diagram showing the operation in the periphery of the TMR element in the memory area
- Fig. 8B is a diagram showing the operation in the periphery of the TMR element in the memory area.
- Fig. 9 is a diagram showing the mamufacturing process of a semiconductor layer.
- Fig. 10 is a diagram showing the mamufacturing process of the semiconductor layer.
- Fig. 11 is a diagram showing the mamufacturing process of a semiconductor layer.
- Fig. 12 is a diagram showing the mamufacturing process of a semiconductor layer.
- Fig. 13 is a diagram showing the mamufacturing process of a semiconductor layer.
- Fig. 14 is a diagram showing the mamufacturing process of a semiconductor layer.
- Fig. 15 is a diagram showing the mamufacturing process of a wiring layer.
- Fig. 16 is a diagram showing the manufacturing process of the wiring layer.
- Fig. 17 is a diagram showing the mamufacturing process of the wiring layer.
- Fig. 18 is a diagram showing the mamufacturing process of the wiring layer.
- Fig. 19 is a diagram showing the mamufacturing process of the wiring layer.
- Fig. 20 is a diagram showing the mamufacturing process of the wiring layer.
- Fig. 21 is a diagram showing the mamufacturing process of the wiring layer
- Fig. 22 is a diagram showing the mamufacturing process of the wiring layer.
- Fig. 23 is a diagram showing the mamufacturing process of the wiring layer.
- Fig. 24 is a diagram showing the mamufacturing process of the wiring layer.
- Fig. 25 is a diagram showing the mamufacturing process of the wiring layer.
- Fig. 26 is a diagram showing the mamufacturing process of the wiring layer.
- Fig. 27 is a diagram showing the mamufacturing process of a magnetic material layer.
- Fig. 28 is a diagram showing the mamufacturing process of the magnetic material layer.
- Fig. 29 is a diagram showing the mamufacturing process of the magnetic material layer.
- Fig. 30 is a diagram showing the mamufacturing process of the magnetic material layer.
- Fig. 31 is a diagram showing the mamufacturing process of the magnetic material layer.
- Fig. 32 is a diagram showing the mamufacturing process of the magnetic material layer.
- Fig. 33 is a diagram showing the mamufacturing process of the magnetic material layer.
- Fig. 34 is a diagram showing the mamufacturing process of the magnetic material layer.
- Fig. 35 is a diagram showing the mamufacturing process of the magnetic material layer.
- Fig. 36 is a diagram showing the mamufacturing process of the magnetic material layer.
- Fig. 37 is a diagram showing a configuration of a magnetic yoke in accordance with a modification.
- Fig. 38 is a diagram showing a configuration of a magnetic yoke in accordance with a modification.
- Fig. 39A is a side sectional view showing an example of a structure of a memory area in a conventional MRAM
- Fig. 39B is a sectional diagram showing a structure of a TMR element.
- Fig. 1 is a diagram schematically showing the entire configuration of a magnetic memory 1 in accordance with the embodiment.
- the magnetic memory 1 includes a memory section 2, a bit selection circuit 11, a word selection circuit 12, bit wirings 13a, 13b, a word wiring 14, and a grounding wiring 15.
- the memory section 2 includes a plurality of memory areas 3.
- the pluralities of memory areas 3 are two-dimensionally disposed including m rows and n columns (m, n are integers of 2 or more).
- Each of the plural memory areas 3 has a magnetic element section 9, which includes a TMR element 4, a write wiring 31 and a read wiring 33, a write transistor 32 and a read transistor 34.
- the TMR element 4 is a magnetoresistive effect element including a magneto-sensitive layer of which magnetizing direction changes depending on the external magnetic field.
- the TMR element 4 configured including a first magnetic layer as a magneto-sensitive layer, a second magnetic layer of which magnetizing direction is fixed, and a nonmagnetic insulating layer sandwiched between the first magnetic layer and the second magnetic layer.
- TMR element 4 is disposed along a part of the write wiring 31 so that the magnetizing direction of the first magnetic layer changes under the external magnetic field, which is generated by the write current flowing through the write wiring 31.
- the resistant value between the first magnetic layer and the second magnetic layer changes in accordance with the relationship between the magnetizing direction of the first magnetic layer and the magnetizing direction of the second magnetic layer.
- the write wiring 31 is a wiring for providing an external magnetic field to the first magnetic layer of the TMR element 4 by means of the write current.
- One end of the write wiring 31 is electrically connected to a bit wiring 13a.
- the other end of the write wiring 31 is electrically connected to the source or the drain of the write transistor 32.
- the write transistor 32 is a semiconductor write switching device for controlling the conduction of the write current in the write wiring 31.
- one of the drain and the source is electrically connected to the write wiring 31 and the other is electrically connected to the bit wiring 13b.
- the gate of the write transistor 32 is electrically connected to the word wiring 14.
- the read wiring 33 is a wiring for flowing a read current through the TMR element 4. Specifically, one end of the read wiring 33 is electrically connected to the bit wiring 13a; and the other end of the read wiring 33 is electrically connected to the first magnetic layer side of the TMR element 4.
- the read transistor 34 is a semiconductor read switching device for controlling the conduction of the read current in the read wiring 33. One of the sources and the drain of the read transistor 34 is electrically connected to the second magnetic layer side of the TMR element 4; and the other of the source and the drain is electrically connected to the grounding wiring 15. The gate of the read transistor 34 is electrically connected to the word wiring 14.
- first magnetic layer side (second magnetic layer side) of the TMR element 4" means the first magnetic layer side or the second magnetic layer side with respect to the nonmagnetic insulating layer including the case being interposed by another layer on the first magnetic layer (second magnetic layer).
- the bit wirings 13a and 13b are disposed for each column of the memory area 3.
- the bit wirings 13a and 13b are the first wirings in this embodiment. That is, the bit wiring 13a is electrically connected to one end of the write wiring 31 included in each of the memory areas 3 in the corresponding column. Further, the bit wiring 13a of the embodiment is electrically connected to one end of the read wiring 33 included in each of the memory area 3 in the corresponding column.
- the bit wiring 13b is electrically connected to the drain or the source of the write transistor 32 included in each of the memory areas 3 in the corresponding column.
- the word wiring 14 is a second wiring in this embodiment. That is, the word wiring 14 is disposed corresponding to each row of the memory areas 3 and is electrically connected to the gate, which is a control terminal of the write transistor 32 included in each memory area 3 in the corresponding row.
- the bit selection circuit 11 is a write current generating device in this embodiment. That is, the bit selection circuit 11 has a function to provide a positive or negative write current to the write wiring 31 in each memory area 3. Specifically, the bit selection circuit 11 is configured including an address decoder circuit, which selects a column corresponding to the address in accordance with the specified address when writing data from the inside or outside of the magnetic memory 1, and a current drive circuit, which supplies a positive or negative write current between the bit wiring 13a and the wiring 13b corresponding to the selected column. Also, the word selection circuit 12 has a function to select a row corresponding to the selected row in accordance with the address specified when writing data from the inside or the outside of the magnetic memory 1 and provide a control voltage to the word wiring 14 corresponding to the address.
- the magnetic memory 1 configured as described above operates as described below. That is, when an address (i-th row j-th column/1 ⁇ i ⁇ m, 1 ⁇ j ⁇ n) to be written with data is specified from the inside or the outside of the magnetic memory 1, the bit selection circuit 11 and the word selection circuit 12 select corresponding j-th column and i-th row respectively.
- the write transistor 32 of a memory area 3 included in the i-th row selected by the word selection circuit 12 a control voltage is impressed to the gate, and a state that the write current is conductive is established.
- a positive or negative voltage is impressed between the bit wiring 13a and the bit wiring 13b in accordance with the data.
- a write current is generated on the write wiring 31 via the write transistor 32, and the magnetizing direction of the first magnetic layer of the TMR element 4 is inverted by the magnetic field of the write current.
- binary data are written in the memory area 3 at the specified address (i-th row, j-th column).
- the bit selection circuit 11 and the word selection circuit 12 select the corresponding 1-th column and k-th row respectively.
- a control voltage is impressed to the gate, and a state that the read current is conductive is established.
- bit wiring 13a corresponding to the 1-th column selected by the bit selection circuit 11 a voltage for flowing a read current is impressed from the bit selection circuit 11.
- the read current from the read wiring 33 flows to the grounding wiring 15 via the TMR element 4 and the read transistor 34. And by determining the amount of the voltage drop in, for example, the TMR element 4, the binary data stored in the memory area 3 at the specified address (k-th row 1-th column) are read out.
- Fig. 2 is an enlarged section showing a sectional configuration when the memory section 2 is cut off along the line direction.
- Fig. 3 is an enlarged section when the memory section 2 is cut off along the line I-I in Fig. 2 .
- Fig. 4 is an enlarged section when the memory section 2 is cut off along the line II-II in Fig. 2 .
- the memory section 2 includes a semiconductor layer 6, a wiring layer 7, a magnetic material layer 8 and an anti-diffusion layer 36.
- the semiconductor layer 6 is a layer, which includes a semiconductor substrate 21 to maintain the mechanical strength of the entire memory section 2, and is formed with an area of semiconductor element such as transistor.
- the magnetic material layer 8 is a layer in which component elements (magnetic element section 9) such as the TMR element 4 and a magnetic yoke 5 including a magnetic material for efficiently giving a magnetic field to the TMR element 4 are formed.
- the wiring layer 7 is formed between the semiconductor layer 6 and the magnetic material layer 8.
- the wiring layer 7 is a layer in which wirings such as the bit wirings 13a, 13b and the word wiring 14 penetrating each memory area 3 are formed. Also, in the wiring layer 7, wirings for electrically connecting the magnetic element section 9 formed in the magnetic material layer 8 to the semiconductor element area such as the transistor formed in the semiconductor layer 6 are formed.
- the anti-diffusion layer 36 is a layer for preventing ferromagnetic material (ferromagnetic element) included in the magnetic element section 9 from diffusing into the semiconductor layer 6.
- the semiconductor layer 6 includes a semiconductor substrate 21, an insulating area 22, a drain area 32a and a source area 32c of the write transistor 32, and a drain area 34a and a source area 34c of the read transistor 34.
- the semiconductor substrate 21 is formed of, for example, a Si substrate doped with a p-type or n-type impurity
- the insulating area 22 is formed in an area other than the write transistor 32 and the read transistor 34 on the semiconductor substrate 21 to electrically separate the write transistor 32 from the read transistor 34.
- the insulating area 22 is formed from an insulation material such as, for example, SiO 2 .
- the read transistor 34 is configured of a drain area 34a and a source area 34c, which are semiconductor areas of a conductive type opposite to that of the semiconductor substrate 21, a gate electrode 34b, and a part of the semiconductor substrate 21.
- the drain area 34a and the source area 34c are, for example, formed adjacent to the surface of the Si substrate being doped with an impurity of conductive type opposite to that of the semiconductor substrate 21.
- the drain area 34a and the source area 34c are interposed by the semiconductor substrate 21 therebetween, on the semiconductor substrate 21, and the gate electrode 34b is disposed being separated therefrom.
- the read transistor 34 when a voltage (control voltage) is applied to the gate electrode 34b, conduction is established between the drain area 34a and the source area 34c.
- the gate electrode 34b is formed, not in the semiconductor layer 6, but in the wiring layer 7, which will be described later.
- the read transistor 32 is configured of a drain area 32a and a source area 32c, which are semiconductor areas of a conductive type opposite to that of the semiconductor substrate 21, a gate electrode 32b, and a part of the semiconductor substrate 21.
- the drain area 32a and the source area 32c are, for example, are formed adjacent to the surface of the Si substrate being doped with an impurity of conductive type opposite to that of the semiconductor substrate 21.
- the drain area 32a and the source area 32c are interposed by the semiconductor substrate 21 therebetween; on the semiconductor substrate 21, the gate electrode 32b is disposed being separated therefrom.
- the read transistor 32 when a voltage (control voltage) is applied to the gate electrode 32b, a conduction is established between the drain area 32a and the source area 32c.
- the gate electrode 32b is formed, not in the semiconductor layer 6, but in the wiring layer 7, which will be described later.
- the magnetic material layer 8 is configured including an insulating area 24 and a magnetic element section 9.
- the magnetic element section 9 includes the TMR element 4, the magnetic yoke 5, the write wiring 31 and the read wiring 33.
- the insulating area 24 occupies the area other than the magnetic element section 9 and other wirings.
- Fig. 5 and Fig. 6 are enlarged views of the TMR element 4 and the periphery structure thereof.
- Fig. 5 shows a section of the memory area 3 along the row direction; and
- Fig. 6 shows a section of the memory area 3 along the column direction. Referring to Fig. 5 and Fig.
- the TMR element 4 configured of a first magnetic layer 41, a nonmagnetic insulating layer 42, a second magnetic layer 43, and an antiferromagnetic layer 44 being piled up in this order.
- the first magnetic layer 41 is the magneto-sensitive layer and the magnetizing direction thereof changes depending on the external magnetic field from the write wiring 31; thus, binary data are recorded.
- a ferromagnetic material such as Co, CoFe, NiFe, NiFeCo and CoPt are available.
- the magnetizing direction is fixed by the antiferromagnetic layer 44. That is, owing to exchange coupling in the joint surface between the antiferromagnetic layer 44 and the second magnetic layer 43 the magnetizing direction of the second magnetic layer 43 is stabilized.
- the easy-to-magnetize axis direction of the second magnetic layer 43 is adapted so as to agree with the easy-to-magnetize axis direction of the first magnetic layer 41.
- a ferromagnetic material such as Co, CoFe, NiFe, NiFeCo and CoPt may be employed.
- a material of the antiferromagnetic layer 44 a material of IrMn, PtMn, FeMn, PtPdMn, NiO, or arbitrary combination thereof may be employed.
- the nonmagnetic insulating layer 42 is a layer formed from a nonmagnetic and insulation material. Being interposed by the nonmagnetic insulating layer 42 between the first magnetic layer 41 and the second magnetic layer 43, tunneling magnetoresistive (TMR) is generated between the first magnetic layer 41 and the second magnetic layer 4. That is, between the first magnetic layer 41 and the second magnetic layer 43, an electrical resistance corresponding to the relative relationship (parallel or anti-parallel) between the magnetizing direction of the first magnetic layer 41 and the magnetizing direction of the second magnetic layer 43 is generated.
- the material of the nonmagnetic insulating layer 42 for example, oxide or nitride of a metal such as Al, Zn and Mg is suitable.
- a third magnetic layer may be formed being interposed by a non-magnetic metal layer or synthetic AF (antiferromagnetic) layer.
- the third magnetic layer forms an antiferromagnetic combine with the second magnetic layer 43, thereby the magnetizing direction of the second magnetic layer 43 is further stabilized. Further, the influence of magnetostatic from the second magnetic layer 43 to the first magnetic layer 41 can be prevented, and the magnetizing direction of the first magnetic layer 41 can be easily inversed.
- the material of the third magnetic layer is not particularly limited, but it is preferred to use a single ferromagnetic material such as Co, CoFe, NiFe, NiFeCo and CoPt or in combination thereof.
- a single ferromagnetic material such as Co, CoFe, NiFe, NiFeCo and CoPt or in combination thereof.
- Ru, Rh, Ir, Cu and Ag are preferable.
- the thickness of the non-magnetic metal layer is preferably 2nm or less so as to obtain a strong antiferromagnetic combine between the second magnetic layer 43 and the third magnetic layer.
- the read wiring 33 is formed on the first magnetic layer 41 of the TMR element 4.
- the read wiring 33 is formed from a conductive metal and extends in the line direction of the memory areas 3.
- One end of the read wiring 33 is electrically connected to the first magnetic layer 41.
- the other end of the read wiring 33 is electrically connected to an electrode 17b via vertical wiring 16f (refer to Fig. 2 ).
- the antiferromagnetic layer 44 of the TMR element 4 is formed on an electrode 35 and electrically connected to the electrode 35. Owing to the above configuration, the read current can be flown from the read wiring 33 to the TMR element 4.
- the write wiring 31 is formed. Between the read wiring 33 and the write wiring 31, a gap is provided and filled with the material of the insulating area 24 to insulate therebetween.
- the write wiring 31 is formed of a conductive metal and extends in the line direction of the memory area 3.
- One end of the write wiring 31 is electrically connected to an electrode 17a via a vertical wiring 16a (refer to Fig. 2 ).
- the other end of the write wiring 31 is electrically connected to an electrode 17c via vertical wiring 16h (refer to Fig. 2 ).
- the easy-to-magnetize axis direction of the first magnetic layer 41 of the TMR element 4 is adapted so as to agree with the direction crossing the longitudinal direction of the write wiring 31 (i.e., direction crossing the direction of the write current).
- the magnetic yoke 5 is a ferromagnetic member, which encloses the periphery of the write wiring 31 and efficiently provides the magnetic field generated by the write current to the TMR element 4.
- the magnetic yoke 5 is formed of a substantially ring-like member, which has at least a pair of open ends facing to each other being interposed by a gap of a predetermined length and is disposed so as to enclose the outer periphery of the write wiring 31 at a portion in the extending direction of the write wiring 31.
- the magnetic yoke 5 of the embodiment includes a pair of opposed yokes 5b, a pair of pillar yokes 5c and a beam yoke 5d.
- the pair of opposed yokes 5b has a pair of end faces 5a as the pair of open ends, and are formed so as to face to each other along the easy-to-magnetize axis direction of the first magnetic layer 41.
- the TMR element 4 is disposed so that the a pair of side faces 4a (refer to Fig. 6 ) faces to a pair of end face 5a, and the easy-to-magnetize axis direction of the first magnetic layer 41 agree with the direction where the pair of end face 5a are aligned.
- the beam yoke 5d is formed along the face of the write wiring 31 opposite to the TMR element 4.
- the pair of pillar yokes 5c is formed along the side faces of the write wiring 31 respectively, and connects between one end of the pair of opposed yokes 5b at the side different from the end face 5a and the both ends of the beam yoke 5d.
- the opposed yokes 5b, the pillar yokes 5c and the beam yoke 5d enclose the outer periphery of the write wiring 31 in a portion in the extending direction of the write wiring 31 (a part on the TMR element 4).
- the material forming the magnetic yoke 5 for example, a metal including at least one element of Ni, Fe and Co is preferred.
- the magnetic yoke 5 is formed so that the easy-to-magnetize axis direction thereof agrees with the easy-to-magnetize axis direction of the first magnetic layer 41 of the TMR element 4.
- the cross sectional area of the magnetic yoke 5 in the faces perpendicular to the peripheral direction of the write wiring 31 the area in the pair of end faces 5a is the smallest.
- the cross sectional area of the opposed yokes 5b is the smallest.
- the cross sectional area of the opposed yokes 5b becomes smaller closer to the end faces 5a.
- an insulation material such as SiO 2 is available.
- the wiring layer 7 includes an insulating area 23, bit wirings 13a and 13b, a word wiring 14, a grounding wiring 15, and a plurality of vertical wirings and horizontal wirings.
- the insulating area 23 occupies the area other than the wirings.
- an insulation material such as SiO 2 is available.
- the material for the vertical wirings for example, W is available.
- the material for the horizontal wiring for example, A1 is available.
- an electrode 17a connected to one end of the write wiring 31 of the magnetic material layer 8 is electrically connected to the bit wiring 13a via the vertical wiring 16b.
- the electrode 35 which is electrically connected to the second magnetic layer 43 side of the TMR element 4, is electrically connected to vertical wirings 16c to 16e and horizontal wirings 18a, 18b of the wiring layer 7.
- the vertical wiring 16e is in ohmic contact with the drain area 34a of the read transistor 34.
- an electrode 17b which is electrically connected to the first magnetic layer 41 side of the TMR element 4 via the read wiring 33, is electrically connected to the horizontal wiring 18c via vertical wiring 16g.
- the horizontal wiring 18c is electrically connected to the bit wiring 13a via an unshown wiring.
- the grounding wiring 15 is electrically connected to a vertical wiring 16n; and the vertical wiring 16n is in ohmic contact with the source area 34c of the read transistor 34.
- a part of the word wiring 14 serves as the gate electrode 34b of the read transistor 34. That is, the gate electrode 34b shown in Fig. 3 is formed using a part of the word wiring 14 extending in the line direction of the , memory area 3. Owing to the above configuration, the word wiring 14 is electrically connected to the control terminal (gate electrode 34b) of the read transistor 34.
- an electrode 17e which is connected to the other end of the write wiring 31 in the magnetic material layer 8, is electrically connected to vertical wirings 16i to 16k and horizontal wirings 18d, 18e in the wiring layer 7.
- the vertical wiring 16k is in ohmic contact with the drain area 32a of the write transistor 32.
- the horizontal wiring 18h is electrically connected to a vertical wiring 16q; and the vertical wiring 16q is in ohmic contact with the source area 32c of the write transistor 32.
- the horizontal wiring 18h is electrically connected to the bit wiring 13b (refer to Fig. 2 ) via an unshown wiring.
- a part of the word wiring 14 serves as the gate electrode 32b of the write transistor 32. That is, the gate electrode 32b shown in Fig. 4 is formed using a part of the word wiring 14 extending in the line direction of the memory area 3. Owing to the above configuration, the word wiring 14 is electrically connected to the control terminal (gate electrode 32b) of the write transistor 32.
- the anti-diffusion layer 36 is a layer for preventing the ferromagnetic material (ferromagnetic element), which is included in the TMR element 4 of the magnetic element section 9, and the magnetic yoke 5 from diffusing into the semiconductor layer 6.
- the anti-diffusion layer 36 is formed between the magnetic material layer 8 and the wiring layer 7.
- the anti-diffusion layer 36 preferably includes a material for preventing the ferromagnetic material from passing through, for example, at least one element selected from a group consisnting of Ti and Ru.
- the anti-diffusion layer 36 is disposed at least between the magnetic material layer 8 and the semiconductor layer 6.
- the anti-diffusion layer 36 may be disposed between the wiring layer 7 and the semiconductor layer 6 or within the wiring layer 7.
- the electrodes 17a to 17c are positioned at the magnetic material layer 8 side with respect to the anti-diffusion layer 36.
- the electrodes 17a to 17c may be positioned at the wiring layer 7 side with respect to the anti-diffusion layer 36.
- Fig. 7A when a negative write current I w1 flows through the write wiring 31, a magnetic field ⁇ 1 is generated around the write wiring 31 in the peripheral direction of the write wiring 31.
- the magnetic field ⁇ 1 forms a closed path, which goes through the inside of the magnetic yoke 5 formed around the write wiring 31 and the gap between the pair of end faces 5a.
- the cross sectional area of the opposed yokes 5b is the smallest. Accordingly, the magnetic flux density of the magnetic field ⁇ 1 formed inside the magnetic yoke 5 is the largest at the opposed yokes 5b.
- the magnetic field ⁇ 1 is generated around the write wiring 31, owing to the magnetic field enclosing effect in the magnetic yoke 5, the magnetic field ⁇ 1 (external magnetic field) is efficiently provided to the first magnetic layer 41 of the TMR element 4. Owing to the magnetic field ⁇ 1 , the magnetizing direction A of the first magnetic layer 41 is oriented to the same direction as that of the magnetic field ⁇ 1 .
- the magnetizing direction B of the second magnetic layer 43 is previously oriented to the same direction as that of the magnetic field ⁇ 1 , the magnetizing direction A of the first magnetic layer 41 and the magnetizing direction B of the second magnetic layer 43 are oriented to the same direction; i.e., parallel to each other.
- one of the binary data. (for example 0) is written in the TMR element 4.
- a read current Ir is flown between the read wiring 33 and the electrode 35, and a change in current value is detected. Or a change of the potential difference between the read wiring 33 and the electrode 35 is detected. Owing to this, it is possible to determine which of the binary data the TMR element 4 records (i.e., whether the magnetizing direction A in the first magnetic layer 41 is parallel or anti-parallel with the magnetizing direction B in the second magnetic layer 43).
- the resistant value between the first magnetic layer 41 and the second magnetic layer 43 is relatively small. Accordingly, assuming that, for example, the read current Ir is constant, the potential difference between the read wiring 33 and the electrode 35 is relatively small, it is determined that the TMR element 4 is written with 0 as the binary data.
- a magnetic field ⁇ 2 when a positive write current I w2 flows through the write wiring 31, a magnetic field ⁇ 2 , of which direction is the opposite to that of the magnetic field ⁇ 1 , is generated around the write wiring 31.
- the magnetic field ⁇ 2 forms a closed path, which goes through the inside of the magnetic yoke 5 and the gap between the pair of end faces 5a.
- the magnetic flux density of the magnetic field ⁇ 2 formed inside the magnetic yoke 5 is the largest at the opposed yokes 5b.
- the magnetic field ⁇ 2 is generated around the write wiring 31, owing to the magnetic field enclosing effect of the magnetic yoke 5, the magnetic field ⁇ 2 (external magnetic field) is efficiently provided to the first magnetic layer 41 of the TMR element 4.
- the magnetizing direction A of the first magnetic layer 41 is oriented to the same direction as that of the magnetic field ⁇ 2 .
- the magnetizing direction B of the second magnetic layer 43 is oriented to the direction opposite to that of the magnetic field ⁇ 2
- the magnetizing direction A in the first magnetic layer 41 and the magnetizing direction B in the second magnetic layer 43 are opposite to each other i.e., anti-parallel with each other.
- the TMR element 4 is written with the other one of the binary data (for example, 1).
- TMR tunneling magnetoresistive
- the magnetic memory 1 As described above, by sandwiching a layer (wiring layer 7) between the layer (magnetic material layer 8) including the TMR element 4 and the layer (semiconductor layer 6) including the write transistor 32, the ferromagnetic material diffused from the TMR element 4 hardly reaches to the semiconductor layer 6.
- the diffusion of the ferromagnetic material into the drain area 32a and the source area 32c of the write transistor 32 is reduced.
- the process forming the magnetic material layer 8 and the process forming the wiring layer 7 and the semiconductor layer 6 can be separated from each other. Owing to this, the TMR element 4 can be formed in a state that the wiring layer 7 protects the write transistor 32. Accordingly, in the manufacturing process, the ferromagnetic material is prevented from mixing into the drain area 32a and the source area 32c of the write transistor 32.
- the above-described magnetic memory 1 can be achieved by providing the write transistor 32 to each memory area 3. That is, unlike the conventional magnetic memory 100 shown in Fig. 39A , by disposing the write transistor 32 to each memory area 3, the write wiring 31, which provides the external magnetic fields ⁇ 1 and ⁇ 2 to the TMR element 4, can be disposed independently to each memory area 3. Accordingly, bit wirings 13a, 13b, which are provided for the plurality of memory areas 3, can be formed being separated from the magnetic material layer 8. Thus, the magnetic material layer 8, the wiring layer 7 and the semiconductor layer 6 can be separated from each other.
- the anti-diffusion layer 36 which prevents the element included in the TMR element 4 from diffusing into the semiconductor layer 6, is formed. Owing to this, it is possible to reduce the diffusion of the ferromagnetic material into the drain area 32a and the source area 32c more effectively. And it is possible more effectively to prevent the ferromagnetic material from mixing into the drain area 32a and the source area 32c in the manufacturing process.
- the read wiring 33 which is provided to each of the plurality of memory areas 3 and electrically connected to the TMR element 4 to flow the read current Ir through the TMR element 4, is included in the magnetic material layer 8.
- the drain area 34a and the source area 34c constituting the read transistor 34, which controls the conduction of the read current Ir are included in the semiconductor layer 6. Owing to this, the binary data stored in the TMR element 4 can be appropriately read out.
- the magnetic memory 1 since the wiring layer 7 is sandwiched between the semiconductor layer 6 and the magnetic material layer 8, it is possible to reduce the diffusion of the ferromagnetic material into the drain area 34a and the source area 34c. Further in the manufacturing process, it is possible to prevent the ferromagnetic material from mixing into the drain area 34a and the source area 34c.
- the magnetic yoke 5 is preferably formed of a ring-like member, which has at least a pair of open ends (end faces 5a) opposing being interposed by a gap of a predetermined length, and disposed so as to enclose the outer periphery of the write wiring 31 at a portion in the extending direction thereof. Owing to this, in the magnetic fields due to the write currents I w1 and I w2 , the magnetic field, which is emitted in the direction away from TMR element 4 can be reduced Further, the magnetic yoke 5 has a pair of end faces 5a each facing to a pair of side faces 4a of the TMR element 4.
- the magnetic fields ⁇ 1 and ⁇ 2 inside the magnetic yoke 5, which forms a path closed in the peripheral direction, can be efficiently provided to the first magnetic layer 41 of the TMR element 4.
- the magnetic fields ⁇ 1 and ⁇ 2 due to the write currents I w1 and I w2 can be provided efficiently to the TMR element 4.
- the magnetizing direction A in the first magnetic layer 41 of the TMR element 4 can be inverted using small write currents I w1 and I w2 .
- the magnetizing direction A of the first magnetic layer 41 can be inverted using small write currents I w1 and I w2 .
- the write transistor 32 for controlling the conduction of the write currents I w1 and I w2 can be miniaturized. Accordingly, the write transistor 32 can be easily disposed to each memory area 3.
- the easy-to-magnetize axis direction of the magnetic yoke 5 preferably agrees with the easy-to-magnetize axis direction of the first magnetic layer 41. Also, it is preferred that the area of the section perpendicular to the peripheral direction in the magnetic yoke 5 is the smallest at the pair of end faces 5a. Owing to this, the magnetic fields ⁇ 1 and ⁇ 2 inside the magnetic yoke 5 can be given to the first magnetic layer 41 of the TMR element 4 more efficiently.
- Fig. 9 to Fig. 26 the forming process of the semiconductor layer and the wiring layer will be described. And then, referring to Fig. 27 to Fig. 37 , the forming process of the magnetic material layer will be described.
- Fig. 9 to Fig. 37 shows a section along the line I-I and II-II in Fig. 2 to illustrate the mamufacturing process sequentially.
- a P-type silicon substrate is prepared as the semiconductor substrate 21.
- a SiO 2 film 61 is formed in a manner of thermal oxidation method.
- a Si 3 N 4 film 62 is formed in a manner of thermal CVD using, for example, SiH and NH 3 as the material gas.
- a resist mask 70 having an opening 70a is formed in a manner of photolithography, and then, in the SiO 2 film 61 and the Si 3 N 4 film 62, openings 61 a and 62a are formed (patterning) in a manner of reactive ion etching (RIE) (refer to Fig. 10 ).
- RIE reactive ion etching
- the exposed portion of the SiO 2 film 61 is oxidized in a manner of thermal oxidation method.
- the field oxide film (i.e., insulating area 22) of SiO 2 is formed.
- the SiO 2 film 61 and the Si 3 N 4 film 62 are removed in a manner of wet etching.
- the gate insulation film 23a of SiO 2 is formed thinly in a manner of thermal oxidation method.
- a polycrystalline silicon film 63 is formed on the gate insulation film 23a.
- the polycrystalline silicon film 63 is formed in a manner of thermal CVD using, for example, SiH and N 2 as the material gas.
- a resist mask having a gate electrode pattern is formed on the polycrystalline silicon film 63, and the polycrystalline silicon film 63 is subjected to an etching in a manner of RIE to form the gate electrode 32b (34b).
- the gate electrode 32b (34b) is formed as a part of the word wiring 14 (refer to Fig. 2 to Fig. 4 ).
- a resist mask having a word wiring pattern is formed on the polycrystalline silicon film 63; and then, the polycrystalline silicon film 63 is subjected to an etching in a manner of RIE to form the word wiring 14.
- the portion other than the portion between the gate electrode 32b (34b) and the semiconductor substrate 21 in the gate insulation film 238 is subjected to RIE using the gate electrode 32b (34b) as the mask to remove therefrom.
- the gate insulation film 23a formed as described above becomes a part of the insulating area 23 (refer to Fig. 2 to Fig. 4 ).
- ion 80 for example As
- ion 80 is injected into the semiconductor substrate 21 using the gate electrode 32b (34b) as the mask; thereby, the n + -type drain area 32a (34a), and the source area 32c (34c) are formed with respect to the gate electrode 32b (34b) in a self aligning manner.
- the semiconductor layer 6 is completed.
- the interlayer insulation film 23c of SiO 2 is formed all over the semiconductor substrate 21 in a manner of CVD using, for example, SiH and O 2 as the material gas.
- the interlayer insulation film 23c also becomes a part of the insulating area 23.
- contact holes 23d to 23f are formed in the interlayer insulation film 23c.
- a resist pattern having openings corresponding to the position and the configuration of the contact holes 23d to 23f is formed on the interlayer insulation film 23c, and the interlayer insulation film 23c is subjected to RIB to form the contact holes 23d to 23f.
- an Al film 64 is formed in a manner of sputtering.
- the Al film 64 is subjected to an etching (RIE) using a resist mask of a predetermined pattern.
- RIE etching
- a wiring 16s electrically connected to the gate electrode 32b (34b) and a wiring 16t electrically connected to the source area 32c (34c) are formed.
- wirings 16r to 16t serve as both of the vertical wiring and the horizontal wiring.
- the vertical wiring portion and the horizontal wiring portion may be formed using different materials (in different process). If necessarily, the wirings 16r to 16t may be omitted. In particular, in the case where the gate electrode 32b (34b) is commonly used as the word wiring 14 (refer to Fig. 1 ), the wiring 16s electrically connected to the gate electrode 32b (34b) is not necessary. Contrarily, in the case where gate electrode 32b (34b) is not used as the word wiring 14, the wiring 16s may be used as the word wiring 14.
- an interlayer insulation film 23g of SiO 2 is formed all over the semiconductor substrate 21 as shown in Fig. 19 .
- the interlayer insulation film 23g also becomes a part of the insulating area 23.
- holes 23h and 23i are formed in the interlayer insulation film 23g by subjecting the interlayer insulation film 23g to an etching (RIE).
- RIE etching
- the W film 65 formed in an area other than the holes 23h and 23i is removed in a manner of chemical mechanical polishing (CMP) to flatten the surface of the interlayer insulation film 23g.
- CMP chemical mechanical polishing
- the vertical wirings 16u and 16v are formed.
- These vertical wirings 16u and 16v are an example of vertical wirings in Fig. 2 to Fig. 4 .
- the vertical wiring may be formed in a predetermined portion using the above-described manufacturing method.
- an A1 film 66 is formed in a manner of sputtering.
- the A1 film 66 is subjected to an etching (RIE) to form horizontal wirings 18i and 18j as shown in Fig. 24 .
- RIE etching
- These horizontal wirings 18i and 18j are an example of the horizontal wirings shown in Fig. 2 to Fig. 4 .
- the horizontal wiring can be formed at a predetermined point using the above manufacturing method.
- bit wirings 13a and 13b disposed through the plurality of memory areas 3 are also formed using the same manufacturing process as that of the horizontal wiring 18i and 18j.
- the vertical wirings and the horizontal wirings are repeatedly formed using the same manner as that in the above-described processes (refer to Fig. 19 to Fig. 24 ); thus, the every wiring within the wiring layer 7 is formed.
- the interlayer insulation film is flattened; thus the forming processes of the wiring layer 7 are completed. That is, as show in Fig.
- the uppermost interlayer insulation film 23i (which becomes a part of the insulating area 23) is formed; the holes 23k and 23m are formed in the interlayer insulation film 23i; and the W film 67 is formed on the interlayer insulation film 23i and inside the holes 23k and 23m.
- the W film 67 formed in an area other than the holes 23k and 23m is removed in a manner of CMP, and the surface of the interlayer insulation film 23i is flattened, and vertical wirings 16w and 16x are formed.
- the wiring layer 7 is completed.
- the flattened surface of the interlayer insulation film 23i becomes interface plane 7a between the forming process of the wiring layer 7 and the forming process of the magnetic material layer 8.
- the electrical connection between the wiring layer 7 and the magnetic material layer 8 in the interface plane 7a can be made using a vertical wiring formed of W.
- the anti-diffusion layer 36 is formed in the magnetic memory 1, after flattening the surface of the interlayer insulation film 23i, on the interlayer insulation film 23i, a film of Ti or Ru is formed in a manner of, for example, sputtering or the like; thereby the anti-diffusion layer 36 can be preferably formed.
- the magnetic material layer forming process will be described.
- the electrode 35 is formed on the vertical wiring 16c of the wiring layer 7, the electrode 35 is formed.
- a high vacuum (UHV) DC sputtering apparatus for example, a base layer of Ta, an IrMn layer, a CoFe layer and an A1 layer are formed in this order.
- the A1 layer is oxidized in a manner of oxygen plasma to form a tunnel insulation layer (i.e., a layer to be the nonmagnetic insulating layer 42 shown in Fig. 5 and Fig. 6 ), and then a CoFe layer and a Ta protection layer are formed.
- a tunnel insulation layer i.e., a layer to be the nonmagnetic insulating layer 42 shown in Fig. 5 and Fig. 6
- the TMR element 4 is formed in a manner of ion milling.
- side face of the TMR element 4 is formed from Si (OC 2 H 5 ) 4 , and a SiO 2 insulating layer 24a is formed on the electrode 35.
- a spatter apparatus for example, after forming a NiFe film 68, the resist mask 71 is removed. Then, as shown in Fig.
- a resist mask 72 corresponding to the configuration of the opposed yokes 5b is formed on the NiFe film 68 and the TMR element 4, and then the NiFe film 68 is formed in a manner of ion milling to form a pair of opposed yokes 5b. After that the resist mask 72 is removed.
- the read wiring 33 is formed being in contact with the upper surface of the TMR element 4.
- an insulating layer 24b of the same material as that of the insulating layer 24a is formed in a manner of CVD.
- a resist mask 73 is selectively formed on the plating foundation film 31a.
- the resist mask 73 having an opening, which is in an area above the TMR element 4 and is wider than the upper surface of the TMR element 4, is formed.
- the entire of the magnetic memory 1 is immersed in a plating bath and carry out a plating treatment using the plating foundation film 31a as the electrode to form the write wiring 31b.
- the resist mask 73 is removed.
- the exposed portion is removed in a manner of milling.
- the write wiring 31 is formed.
- an insulating layer 24c of the same material as that of the insulating layers 24a and 24b is formed on the write wiring 31 and the insulating layer 24b in a manner of CVD.
- the resist mask 74 is formed selectively.
- the resist mask 74 is formed in an area, which is above the write wiring 31 and slightly wider than the upper surface of the write wiring 31.
- the portion uncovered by the resist mask 74 is removed in a manner of RIE or the like to expose the opposed yokes 5b. Then, the resist mask 74 is removed (refer to Fig. 34 ).
- the resist mask 75 is formed selectively.
- the resist mask 75 is formed so as not to cover the opposed yokes 5b and the write wiring 31.
- the pair of pillar yokes 5c and the beam yoke 5d are formed in a manner of sputtering.
- the magnetic yoke 5 including the pair of opposed yokes 5b, the pair of pillar yokes 5e, and the beam yoke 5d is formed. Last of all, as shown in Fig.
- the resist mask 75 is removed, and an insulating layer 24d of the same material as that of the insulating layer 24a is formed on the insulating layer 24a and the magnetic yoke 5 in a manner of CVD.
- the insulating area 24 is formed and the magnetic material layer 8 is completed.
- the process in which the drain area 32a and the source area 32b of the write transistor 32 are formed in the semiconductor layer 6, the process in which the bit wirings 13a and 13b and the word wiring 14 are formed on the wiring layer 7 on the semiconductor layer 6 and the process in which the TMR element 4 and the magnetic yoke 5 are formed on the magnetic material layer 8 are perfectly separated from each other. Owing to this, when the TMR element 4 and the magnetic yoke 5 are formed in the magnetic material layer 8, the wiring layer 7 shuts off the ferromagnetic material; thus, the ferromagnetic material is effectively prevented from mixing into the drain area 32a and the source area 32b of the write transistor 32.
- the semiconductor layer forming process, the wiring layer forming process and the magnetic material layer forming process are separated from each other, the semiconductor layer 6, the wiring layer 7 and the magnetic material layer 8 can be designed as a module, respectively. Accordingly, the manufacturing process can be more simplified.
- Fig. 37 and Fig. 38 show a sectional view respectively illustrating the configuration of magnetic yokes 51 and 52 in accordance with the modification.
- the magnetic yoke 51 is configured including a pair of opposed yokes 51b, a pair of pillar yokes 51c, and a beam yoke 51d.
- the constitution and configuration of the pair of pillar yokes 51c and the beam yoke 51d are the same as the constitution and configuration of the above-described pair of pillar yokes 5c and the beam yoke 5d of the magnetic yoke 5 (refer to Fig. 6 ).
- the pair of opposed yokes 51b in the side faces 4a of the TMR element 4, the end face 51a thereof is in contact with the side faces of the first magnetic layer 41.
- the magnetic yoke 51 may have such a configuration as described above; thereby, the magnetic field generated inside the magnetic yoke 51 by a write current can be provided to the first magnetic layer 41 more efficiently.
- a magnetic yoke 52 is configured including a first beam yoke 52b, a pair of pillar yokes 52c and a second beam yoke 51d.
- the first beam yoke 52b is disposed between the read wiring 33 and the nonmagnetic insulating layer 42 so as to serve commonly as the first magnetic layer of the TMR element 4b.
- One end of the first beam yoke 52b is continued to one of a pair of pillar yokes 52c, the other end of the first beam yoke 52b is continued to the another one of the pair of the pillar yokes 52c.
- the beam yoke 52d is formed along the surface at the side opposite to the TMR element 4 in the write wiring 31.
- the pair of pillar yokes 52c are formed along the side faces of the write wiring 31 to connect the both ends of the first beam yoke 52b and the both ends of the second beam yoke 52d.
- the first beam yoke 52b, the pair of pillar yoke 52c and the second beam yoke 52d completely enclose the outer periphery of the write wiring 31 at a portion of the write wiring 31 in the extending direction thereof (a portion on the TMR element 4). Accordingly, the magnetic field generated inside the magnetic yoke 52 by the write current can be provided more efficiently to the first magnetic layer (i.e., to the first beam yoke 52b).
- the magnetic memory in accordance with the present invention is not limited to the above-described embodiment, but various modifications thereof are possible.
- the magnetoresistive effect element the TMR element is used.
- a GMR element utilizing giant magnetoresistive (GMR) effect may be employed.
- the GMR effect means a phenomenon such that, when the angle formed by the two magnetizing directions of the ferromagnetic layers sandwiching a nonmagnetic layer changes, the resistant value of the ferromagnetic layers in the direction perpendicular to the build-up direction thereof changes.
- the resistant value of the ferromagnetic layers becomes the minimum; and when the two magnetizing directions of the ferromagnetic layers are anti-parallel to each other, the resistant value of the ferromagnetic layers becomes the maximum.
- a pseud-spin-valve type in which write/read is carried out using the difference in coercive force between two ferromagnetic layers
- a spin-valve type in which the magnetizing direction of one ferromagnetic layer is fixed by the exchange coupling with the antiferromagnetic layer are available.
- the data read is carried out by detecting the change of the resistant value in the ferromagnetic layer in the direction perpendicular to the build-up direction.
- the data write is carried out by inverting the magnetizing direction of one ferromagnetic layer using the magnetic field generated using a write current.
- the magnetic yoke is formed integrally from one end face to the other end face in the peripheral direction of the write wiring.
- the configuration of the magnetic yoke in addition to the above, for example, such a configuration that one or more gaps are included in the peripheral direction and the magnetic yoke is divided into a plurality of parts may be employed.
- transistors are provided as the semiconductor write switching device and the semiconductor read switching device.
- the switching devices various semiconductor devices, which have a function to turn ON/OFF the current upon the necessity, may be employed.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Nanotechnology (AREA)
- Computer Hardware Design (AREA)
- Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Theoretical Computer Science (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mram Or Spin Memory Techniques (AREA)
- Hall/Mr Elements (AREA)
- Semiconductor Memories (AREA)
Claims (5)
- Magnetischer Speicher (1) mit mehreren Speicherbereichen (3), die einen zweidimensionalen Aufbau aus m Reihen und n Spalten aufweisen, wobei m gleich 2 ist oder einer anderen ganzen Zahl entspricht und n gleich 2 ist oder einer anderen ganzen Zahl entspricht, und jeder Speicherbereich umfasst:Eine magnetische Materialschicht (8) mitEinem magnetwiderstandsbeständigen Element (4), das eine für ein Magnetfeld empfindliche Schicht (41) aufweist, deren Magnetisierungsrichtung sich in Abhängigkeit eines externen Magnetfeldes ändert, und eine Schreibverdrahtung (31), um mithilfe des Schreibstroms ein externes Magnetfeld an die für ein Magnetfeld empfindliche Schicht anzulegen;Einer Halbleiterschicht (6), die einen Halbleiterbereich aufweist, der eine Halbleiterschreibschalteinrichtung (32) zur Steuerung einer Leitung des Schreibstroms in der Schreibverdrahtung (31) bildet;dadurch gekennzeichnet, dass jeder Speicherbereich des Weiteren umfasst:Eine Verdrahtungsschicht (7), die zwischen der magnetischen Materialschicht und der Halbleiterschicht angeordnet ist, wobei die Verdrahtungsschicht umfasst.Eine erste Verdrahtung (13a, 13b), die mit der Schreibverdrahtung (31) elektrisch verbunden ist; undEine zweite Verdrahtung (14), die mit einem Steueranschluss der Halbleiterschreibschalteinrichtung (32) elektrisch verbunden ist.
- Magnetischer Speicher nach Anspruch 1, der des Weiteren eine Antidiffusionsschicht umfasst, die zwischen der magnetischen Materialschicht und der Halbleiterschicht ausgebildet ist, um zu verhindern, dass sich ein in dem magnetwiderstandsbeständigen Element enthaltenes Element in der Halbleiterschicht ausbreitet.
- Magnetischer Speicher nach Anspruch 2, wobei die Antidiffusionsschicht zumindest ein Element, das aus einer Gruppe bestehend aus Ti und Ru ausgewählt wurde, umfasst.
- Magnetischer Speicher nach Anspruch 1, wobei die magnetische Materialschicht des Weiteren eine Leseverdrahtung, die mit dem magnetwiderstandsbeständigen Element elektrisch verbunden ist, umfasst, so dass ein Lesestrom zu dem magnetwiderstandsbeständigen Element fließen kann, und wobei die Halbleiterschicht des Weiteren einen Halbleiterbereich umfasst, der eine Halbleiterleseschalteinrichtung zur Steuerung einer Leitung des Lesestroms in der Leseverdrahtung aufweist.
- Fertigungsverfahren eines magnetischer Speicher (1) mit mehreren Speicherbereichen (3), die einen zweidimensionalen Aufbau aus m Reihen und n Spalten aufweisen, wobei m gleich 2 ist oder einer anderen ganzen Zahl entspricht und n gleich 2 ist oder einer anderen ganzen Zahl entspricht, wobei das Verfahren folgende Schritte umfasst:Bilden einer Halbleiterschicht (6);Bilden einer Verdrahtungsschicht (7) auf der Halbleiterschicht; undBilden einer magnetischen Materialschicht (8) auf der Verdrahtungsschicht, wobeiDas Bilden einer Halbleiterschicht (6) das Bilden eines Halbleiterbereiches umfasst, der eine Halbleiterschreibschalteinrichtung (32) in jedem Speicherbereich der Halbleiterschicht (6) bildet,Das Bilden einer Verdrahtungsschicht (7) das Bilden einer ersten Verdrahtung (13a, 13b), die jeder Spalte des Speicherbereiches entspricht, und einer zweiten Verdrahtung (14) umfasst, die jeder Reihe des Speicherbereiches entspricht und mit einem Steueranschluss der Halbleiterschreibschaltungseinrichtung (32) verbunden ist, die in jedem Speicherbereich (3) in der entsprechenden Reihe der Verdrahtungsschicht (7) ausgebildet ist, undDas Bilden einer magnetischen Materialschicht (8) das Bilden eines magnetwiderstandsbeständigen Elements (4) umfasst, das eine für ein Magnetfeld empfindliche Schicht (41) aufweist, die in jedem Speicherbereich (3) vorgesehen ist und deren Magnetisierungsrichtung sich in Abhängigkeit eines externen Magnetfeldes ändert, und eine Schreibverdrahtung (31), die in jedem Speicherbereich (3) ausgebildet und mit der ersten Verdrahtung (13a, 13b) elektrisch verbunden ist, um mithilfe des Schreibstrom ein externes Magnetfeld an die für ein Magnetfeld empfindliche Schicht (41) anzulegen.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2004260160A JP4569231B2 (ja) | 2004-09-07 | 2004-09-07 | 磁気メモリ及びその製造方法 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP1632951A1 EP1632951A1 (de) | 2006-03-08 |
EP1632951B1 true EP1632951B1 (de) | 2008-02-27 |
Family
ID=35447875
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP05019439A Expired - Fee Related EP1632951B1 (de) | 2004-09-07 | 2005-09-07 | Magnetische Speicherzelle und Methode zu Herstellung derselben |
Country Status (5)
Country | Link |
---|---|
US (1) | US7470964B2 (de) |
EP (1) | EP1632951B1 (de) |
JP (1) | JP4569231B2 (de) |
CN (1) | CN1758371A (de) |
DE (1) | DE602005004965T2 (de) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5056847B2 (ja) * | 2007-03-09 | 2012-10-24 | 富士通株式会社 | 不揮発性半導体記憶装置及びその読み出し方法 |
US7813210B2 (en) * | 2007-08-16 | 2010-10-12 | Unity Semiconductor Corporation | Multiple-type memory |
US8494430B2 (en) * | 2009-09-10 | 2013-07-23 | Xerox Corporation | Apparatus and method for the registration and de-skew of substrate media |
JP5551129B2 (ja) * | 2011-09-07 | 2014-07-16 | 株式会社東芝 | 記憶装置 |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5679982A (en) * | 1993-02-24 | 1997-10-21 | Intel Corporation | Barrier against metal diffusion |
DE10020128A1 (de) | 2000-04-14 | 2001-10-18 | Infineon Technologies Ag | MRAM-Speicher |
JP4309075B2 (ja) | 2000-07-27 | 2009-08-05 | 株式会社東芝 | 磁気記憶装置 |
US6487110B2 (en) * | 2000-09-27 | 2002-11-26 | Canon Kabushiki Kaisha | Nonvolatile solid-state memory device using magnetoresistive effect and recording and reproducing method of the same |
JP2002368196A (ja) | 2001-05-30 | 2002-12-20 | Internatl Business Mach Corp <Ibm> | メモリセル、記憶回路ブロック、データの書き込み方法及びデータの読み出し方法 |
JP3898556B2 (ja) | 2002-04-22 | 2007-03-28 | 株式会社東芝 | 磁気ランダムアクセスメモリ |
JP3906139B2 (ja) * | 2002-10-16 | 2007-04-18 | 株式会社東芝 | 磁気ランダムアクセスメモリ |
JP3980990B2 (ja) | 2002-10-31 | 2007-09-26 | 株式会社東芝 | 磁気メモリ |
JP2004153181A (ja) * | 2002-10-31 | 2004-05-27 | Toshiba Corp | 磁気抵抗効果素子および磁気メモリ |
JP3906145B2 (ja) | 2002-11-22 | 2007-04-18 | 株式会社東芝 | 磁気ランダムアクセスメモリ |
-
2004
- 2004-09-07 JP JP2004260160A patent/JP4569231B2/ja not_active Expired - Fee Related
-
2005
- 2005-09-06 US US11/218,490 patent/US7470964B2/en not_active Expired - Fee Related
- 2005-09-07 EP EP05019439A patent/EP1632951B1/de not_active Expired - Fee Related
- 2005-09-07 CN CNA2005100987743A patent/CN1758371A/zh active Pending
- 2005-09-07 DE DE602005004965T patent/DE602005004965T2/de not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
US20060056232A1 (en) | 2006-03-16 |
JP2006080164A (ja) | 2006-03-23 |
CN1758371A (zh) | 2006-04-12 |
DE602005004965T2 (de) | 2009-03-12 |
US7470964B2 (en) | 2008-12-30 |
EP1632951A1 (de) | 2006-03-08 |
DE602005004965D1 (de) | 2008-04-10 |
JP4569231B2 (ja) | 2010-10-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN100481518C (zh) | 自旋晶体管 | |
US6864551B2 (en) | High density and high programming efficiency MRAM design | |
KR101154468B1 (ko) | 고체 메모리 장치와 고체 메모리 셀의 배열 방법 | |
US7238540B2 (en) | Magnetic random access memory and method of manufacturing the same | |
JP2005044847A (ja) | 磁気抵抗効果素子、磁気記憶セルおよび磁気メモリデバイスならびにそれらの製造方法 | |
US7016221B2 (en) | Magnetoresistive effect element, magnetic memory device and method of fabricating the same | |
EP1632951B1 (de) | Magnetische Speicherzelle und Methode zu Herstellung derselben | |
JP4729836B2 (ja) | 磁気記憶セルおよび磁気メモリデバイスならびに磁気メモリデバイスの製造方法 | |
US7683446B2 (en) | Magnetic memory using spin injection flux reversal | |
WO2006059641A1 (ja) | 磁気メモリ | |
JP4720067B2 (ja) | 磁気記憶セルおよび磁気メモリデバイスならびに磁気メモリデバイスの製造方法 | |
TW202312525A (zh) | 磁性記憶體裝置 | |
CN100458967C (zh) | 磁存储单元以及使用了该单元的磁存储器件 | |
JP2006173472A (ja) | 磁気記憶装置およびその製造方法 | |
EP1635356A1 (de) | Magnetischer Speicher mit Magnetjoch | |
JP2007123512A (ja) | 磁気記憶装置 | |
JP4544396B2 (ja) | 磁気記憶セルおよび磁気メモリデバイス | |
JP2008047840A (ja) | 磁気抵抗効果素子、磁気ランダムアクセスメモリ、及びそれらの製造方法 | |
JP2006165185A (ja) | 磁気メモリ | |
JP2006128220A (ja) | 磁気メモリ | |
JP4556385B2 (ja) | 磁気メモリデバイスの製造方法 | |
JP2006100736A (ja) | 磁気メモリ |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR |
|
AX | Request for extension of the european patent |
Extension state: AL BA HR MK YU |
|
17P | Request for examination filed |
Effective date: 20060908 |
|
AKX | Designation fees paid |
Designated state(s): AT DE |
|
17Q | First examination report despatched |
Effective date: 20061018 |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): DE |
|
REF | Corresponds to: |
Ref document number: 602005004965 Country of ref document: DE Date of ref document: 20080410 Kind code of ref document: P |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20080730 Year of fee payment: 4 |
|
26N | No opposition filed |
Effective date: 20081128 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20100401 |